Field of the Invention
The present invention relates generally to the support of composite barrel segments during manufacture and assembly. More particularly, the present invention relates to a system and method for supporting and stabilizing the edges of composite barrel segments, such as aircraft fuselage segments, during the assembly process.
Related Art
In recent years, aircraft manufacturers have developed aircraft designs and aircraft fabrication methods that make greater use of carbon fiber composite materials and the like (“composite materials” or “CFCM”), such as graphite/epoxy and carbon fiber reinforced plastic (“CFRP”). Composite materials are significantly lighter than traditional aircraft materials (e.g. aluminum, titanium, steel and alloys of these), and can provide high strength with low weight, allowing lighter, more fuel efficient aircraft. In some newer aircraft, for example, the majority of the primary structure, including the fuselage and wing, is made of composite materials. By volume, some new aircraft can be about 80% composite materials.
Since composite materials have different characteristics than some traditional aircraft materials, new facilities, equipment and handling methods have been developed. For example, whereas traditional aircraft manufacturing involves attaching fuselage skin sections (e.g. aluminum sheets) to a metal aircraft frame, large barrel-shaped fuselage sections of composite material can be built as a single unit on an inner mold line mandrel. Such fuselage sections can be quite large, and are typically fabricated without an internal frame. After curing of the composite material, the inner mandrel is removed, and the fuselage section can be assembled with other fuselage sections.
Since structures fabricated from composite materials have different characteristics than many traditional aircraft materials, new equipment and methods have been developed for carrying and holding such structures after removal from a mandrel. One challenge presented by devices for holding and transporting large, frameless composite barrel sections after removal from a mandrel is controlling the shape of the barrel within geometric tolerances during subsequent manufacturing operations or during storage. This challenge relates particularly to the ends of such composite barrel segments.
The present application seeks to address one or more of the above issues.